92' Accord EX Engine Light, Code 13...

We have a 92' Accord 2-dr EX Coupe Automatic with 171,000 miles. The check engine light came on the other day. Flashes code 13 (Atmospheric Pressure Sensor). According to the manual and the tech at the local dealership that you have to replace the entire ECU because the sensor is built into it. At the dealer it runds a hefty price of $970.00. I found one new for $720.00. Still that is pretty expensive. Have any of you had delaings with this code? What are your thoughts? And with this sensor being out it causes the car in 3rd gear once above 51mph to have a terrrible stumble.

Thank you,

Jason